Suction horn



June 28, 1932. c HEATH I 1,865,006

' SUCTION HORN Filed Jan 26, 1952 INVENTOR. 7 #MW 6. HEATH.

B Y 7 A I v Patented June 1932 HARRY G. HEATH, OF SAN FRANCISCO, CALIFORNIA SUCTION HORN Application filed January 26, 1932. Serial No. 588,899.

This invention relates to pneumatic horns as principally used for automobiles, and has for its object an improved construction in suction-operated horns whereby a better note with lessvacuum is obtained, and also which will provide externally accessible means for manually adjusting the note. Another feature is an'extreme compactness of design so as to take up little space. Other features of advantage will appear in the following description and accompanying drawing.

the complete horn.

Fig. 2 is an enlarged cross section of the horn as seen from the line 2-2 of Fig. 1.

Fig. 3 is a detached view on one-half of the horn as seen from the line 3-'3 of Fig. 2 to show its internal spiral shape. Fig. 4 is a plan view of the valve attached to the center of the flexible diaphragm. Fig. 5 -'s a perspective view of the ratchet washer controlling the tension adjustment.

Fig. 6 is an enlarged sectional view of the diaphragm valve. v

In the drawing Fig.- 1 is a side elevation of" In further detail the device comprises a A horn made -'of two'sections 1, 1 bolted or otherwise secured together as at 3. The complementary halves of the horn are preferably spirally shaped as shown in Fig. 3 with a gradually increasing size sound and air passage 4 terminating outwardly in a flared open end 4, and inwardly making a right angle turn 5 communicating with a circular cavity or chamber 6 formed centrally in the outer side of section 1 and over which cavity is bolted, or otherwise secured, a bonnet member 7 formed with a coinciding circular cavity 8 and between which bonnet and horn member 1 is clamped a soft flexible diaphragm 9 preferably made of textile material such as' airplane cloth, or otherwise rendered non-porous as by oil treating or varnishing, or the diaphragm may be of thin flexible leather so treated. I '45 Attached to the center of this soft flexible diaphragm is a circular valve seat 10 as best shown in Fig. 6 and which comprises a round relatively large shallow cup with a hub 11 passing through the diaphragm and a securing flange 12 screwed over the hub or otherwise secured thereto clamping the diaphragm tlghtly between the cup and the flange. The

cup is drilled with several holes 13 and it is resiliently forced outward (away from the bonnet) by means of a light helically coiled wire compression spring 14bearing atits small end against the flange or hub of the valve, while limiting the outward movement of the valve seat is a thin flat valve disk 15 preferably of non-metallic material such as bakelite,

thin fiber sheet, or other slightly flexible though stiff substance, and which valve disk is of a size to lie against and overlap the rim 10 of the valve seat so as to close the same.

This disk 15 is secured to the end of a threaded rod or screw 16 which extends axially and freely through the central hub aperture 17 of the valve and threadedly through the outer wall 7' of the bonnet where it is provided with a thumb nut 18 to permit manual adjustment of the screw to move the disk 15 in-or out for varying the adjustment of the parts and tension of spring 14, and therefore the note produced.

Surrounding this screw and within spring 14 is a helical compression spring 19 POSI- tioned in a central extension or bore 8 of recess 8 arranged to react between the hub of the valve and the bonnet, or rather a fluted washer 20 splined as at 21 to the screw and bearing against a similar fluted washer 22 firmly seated in the bonnet, so that'as the screw is turned the washer 20 will snap over the flutes in the fixed washer 22 and then act as a detent to hold the screw in any position of adjustment.

From bore 8 extends a suction port 23 which is connected by a pipe or hose 24 with any suitable source of suction, such as an exhausted tank or the intake manifold of an internal combustion engine.

Tosecure the born to the frame of an automobile or other support I provide one or more lugs 25 apertured as at 26 for bolting in place. Within valve chamber 6 and extending entirely across the same at a point to clear the indicated.

If desired, this strainer may be omitted and the strainer'placed further .out 1n the horn air passage as at 28 in Fig. 3 wherein it 1s sprung into a groove 29 formed around the walls of the passage, or both strainers may be used, the outer one of a coarser weave. The screen is important in keeping out dirt and bugs which might otherwise lodge between the disk 15 and the valve rim 10. I

In operation, when a valve (not shown) is opened in suction pipe 24 so as to produce suction inchamber 8, its effect on the large diaphragm 9 is to pull it and its attachedvalve seat inwardly into the recess or chamber 8 of the bonnet and thus crack the valve to destroy the vacuum by inrush of air through the horn so that the valve disk will at once reseat through force of sprin 14. The employment of a fabric or the like iaphragm results in a wobbling action to the diaphragm not obtained with stiff metallic diaphragms. Also a much more sensitive and easier action with a lower vacuum. This sensitive action is contributed to.by having the valve disk 1 5 of flexible non-metallic material as it provides a resilient seat for the valve so that it bounces open the' moment it closes and thus sets up a high speed vibratory action and a piercing note.

The quality of the note may be changed by simply turning the thumb screw 18 and thereby putting more or less tension against the spring 14 and therefore affect its yielding to the suction applied to the inner surface of the flexible diaphragm.

I am aware of similarly operated horns, but not with the soft diaphragm to induce wobble of the valve seat, nor of the externa adjustment feature, nor the use of a coiled horn in such a combination with the diaphragm against one side, nor the flexible nonmetallic valve disk, or other features as claimed hereunder.

I claim 1. A horn having a sound passage formed at its inner end with an opening extending substantially at right angles to the axis of the sound passage, a flexible diaphragm secured across said opening and a valve openin in said diaphragm, means for closin said va ve opening, and means for pneumatically moving said diaphragm for cracking the valve.

2. A horn having a sound'passage formed at its inner end with an opening extending substantially at right angles to .the axis of the sound passage, a flexible diaphragm se cured across said opening and a' valve opening in said diaphragm, means for closing said valve opening, means for pneumatically moving said diaphragm for cracking the valve; said diaphragm having substantially no restoring resiliency, and a spring arranged to restore said diaphragm. e

3. A horn having a sound passage formed at itsinner end with an opening extending substantially at right angles to the axls of the sound passage, a flexible diaphragm secured across said opening and a valve opening in said diaphragm, means for closing said valve opening, means for pneumatically moving said diaphragm for cracking the valve, said diaphragm having substantially no restoring resiliency, a spring arranged to re store said diaphragm, and means for limltlng the return movement of said diaphragm.

4. A horn having a sound passage formed at its inner end with an opening extending substantially at right angles to the axis of the sound passage, a flexible diaphragm secured across said opening and a valve opening in said diaphragm, means for closing said valve opening, means for pneumatically moving said diaphragm for cracking the valve, said diaphragm having substantially no restoring resiliency, a spring arranged to restore said diaphragm, and 'means for limiting the return movement of said diaphragm accessible at the outside of the'horn for manual manipulation. h 5. A horn having a spirally shaped sound passage formed at its inner end with an opening extending substantially at right angles to the axis of the sound passage, a flexible diaphragm secured across said opening and a valve opening in said diaphragm, means for closing said valve opening, and means for pneumatically moving said diaphragm for cracking the valve.-

6. A horn body having sound passage with its inner end extending substantially at right angles with the axis of the passage and opening into an enlarged chamber formed in the side of the horn body, a bonnet secured to the side of the horn body over said chamber, a flexible diaphra secured across thechamber between the onnet andthe horn body, a valve carried by the diaphragm forming an air passage through the diaphragm, a valve closure carried by a stem projecting through said air passage, and means foradjusting the position of the valve closure. 7 7. A horn body having a spirally shaped sound passage with its inner end extending substantially at right angles with the axis of the passage and opening into an enlarged chamber formed in the side of the horn body, a bonnet secured to the side of the horn body over said'chamber, a flexible-diaphragm se cured across the chamber between the bonnet and the horn body, a valve carried by the diaphragm forming an air passage through the diaphragm, a valve closure carried by a stem projecting through said air passage, and means for adjusting the position of the valve closure located at a point accessible for manual manipulation.

a spirally shaped 8. A horn provided with an air chamber at secured across said chamber, a valve seat secured to the diaphragm and ported to pass air from one side to the other, a spring resiliently forcing said valve seat in one direction transversely of the plane of the diaphragm, a valve disk arranged to close against said seat, and means for causing an unbalanced air pressure on one side of said diaphragm to crack the seating of the valve disk.

9. A horn provided with an air chamber at its inner end, a diaphragm of soft material secured across said chamber, a valve seat secured to the diaphragm and ported to pass air from one side to the other, a spring resiliently forcin said valve seat in one direction transverse y of the plane of the diaphragm, a. valve disk arran ed to close against said seat, a stem supportm said disk passing through said valve seat an provided with means for adjusting the position of the disk, and means for causing an unbalanced air pressure on one side of said diaphragm to crack the seating of the valve disk..

10. In a structure as specified in claim 8, said disk made of a thin sheet of resilient nonmetallic material.

11. In a structure asspecified in claim 8,

said disk made of a thin sheet 0f bakelite material.

12. In a structure as specified in claim 9, means for locking said stem in adjusted position.

13. In a structure as specified in claim 9, means for locking said stem in adjusted L ition comprisingl a spring-actuated frictional detent surroun ing said stem.

14. In a pneumatic horn of the resilient character described, a diaphragm provided with a central opening and valve seat therearound, valve means for closing the opening, and means supporting the members for relative wobblin motion of the seat and valve means for opemn and closing the valve, and means for disturbmg the equilibrium of the air operative on the diaphragm to cause. such wobbling of the valve. I

15. In a structure as specified in claim 9, a filter screen across the air chamber to the ,outerside of said disk.

16. In a structure as s cified in claim 9, a filter screen disk across t e air chamber to the outer side of said disk seated at its edges in a groove formed in the wall of the chamber.

17. In a structure as specified in claim 8,

said valve seat comprising a shallow cup-like member with a central aperture and a plurality of apertures spaced around the central aperture.

3 may 0. HEATH. 

